Bob Moler's Ephemeris Blog

This is Bob Moler with Ephemeris for Monday, July 1st. Today the Sun will be up for 15 hours and 30 minutes, setting at 9:31, and it will rise tomorrow at 6:02. The Moon, 3 days past last quarter, will rise at 2:50 tomorrow morning.

Let’s preview July’s skies. The Sun, having reached its northern solstice, is beginning to slide southward again, at first imperceptibly, then with greater speed. The daylight hours will decrease from 15 hours and 30 minutes today to 14 hours 40 minutes at month’s end. The daylight hours will be slightly shorter south of Interlochen, and slightly longer to the north. The altitude of the Sun at local noon, when it is due south will decrease from 68 degrees tomorrow to 63 degrees at month’s end. Despite the warmth, the Earth will reach its greatest distance from the Sun on Friday the 5th. Finally, a planet in the evening sky. Saturn will rise before midnight by mid-month, and Venus may be visible shortly after sunset by month’s end.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT–4 hours). They may be different for your location.

Addendum

July Evening Star Chart

The planets and stars are plotted for the 15th at 11 p.m. EDT in the evening and 4 a.m. for the morning chart. These are the chart times. Note that Interlochen/Traverse City is located approximately 45 minutes behind our time meridian, West 75° longitude. (An hour 45 minutes behind our daylight saving time meridian during EDT). To duplicate the star positions on a planisphere you may have to set it to 1 hour 45 minutes earlier than the current time.
Note, the chart times of 11 p.m. and 4 a.m. are for the 15th. For each week before the 15th, add ½ hour (28 minutes if you’re picky). For each week after the 15th, subtract ½ hour, or 28 minutes. The planet positions are updated each Wednesday on this blog. For planet positions on dates other than the 15th, check the Wednesday planet posts on this blog for weekly positions.

July Morning Star Chart

For a list of constellation names to go with the abbreviations, click here.

• Pointer stars at the front of the bowl of the Big Dipper point to Polaris, the North Star.
• Leaky dipper drips on Leo.
• Follow the arc of the handle of the Big Dipper to the star Arcturus, and
• Extend like a spike to Spica.
• The Summer Triangle is in red.
• DAqR is the radiant of the South Delta Aquariid meteor shower (Peaks on the afternoon of the 27th)

Twilight Limits, Nautical and Astronomical

			EDT
	Morning	Twilight	Evening	Twilight	Dark	Night	Moon
Date	Astro.	Nautical	Nautical	Astro.	Start	End	Illum.
2024-07-01	3h35m	4h38m	23h00m	0h02m	0h02m	2h22m	0.16
2024-07-02	3h36m	4h38m	22h59m	0h01m	0h01m	2h51m	0.09
2024-07-03	3h37m	4h39m	22h59m	0h01m	0h01m	3h27m	0.04
2024-07-04	3h39m	4h40m	22h58m	0h00m	0h00m	3h39m	0.01
2024-07-05	3h40m	4h41m	22h58m	23h59m	23h59m	3h40m	0.00
2024-07-06	3h41m	4h42m	22h57m	23h58m	23h58m	3h41m	0.02
2024-07-07	3h43m	4h43m	22h56m	23h57m	23h57m	3h43m	0.05
2024-07-08	3h44m	4h44m	22h56m	23h55m	23h55m	3h44m	0.11
2024-07-09	3h46m	4h45m	22h55m	23h54m	23h54m	3h46m	0.17
2024-07-10	3h47m	4h46m	22h54m	23h53m	–	3h47m	0.25
2024-07-11	3h49m	4h47m	22h53m	23h52m	0h11m	3h49m	0.34
2024-07-12	3h51m	4h48m	22h52m	23h50m	0h27m	3h51m	0.43
2024-07-13	3h52m	4h50m	22h51m	23h49m	0h42m	3h52m	0.53
2024-07-14	3h54m	4h51m	22h50m	23h47m	0h59m	3h54m	0.62
2024-07-15	3h56m	4h52m	22h49m	23h46m	1h18m	3h56m	0.71
2024-07-16	3h58m	4h53m	22h48m	23h44m	1h41m	3h58m	0.80
2024-07-17	3h59m	4h55m	22h47m	23h42m	2h10m	3h59m	0.88
2024-07-18	4h01m	4h56m	22h46m	23h41m	2h49m	4h01m	0.94
2024-07-19	4h03m	4h57m	22h45m	23h39m	3h41m	4h03m	0.98
2024-07-20	4h05m	4h59m	22h44m	23h37m	–	–	1.00
2024-07-21	4h07m	5h00m	22h42m	23h36m	–	–	0.99
2024-07-22	4h09m	5h01m	22h41m	23h34m	–	–	0.96
2024-07-23	4h10m	5h03m	22h40m	23h32m	–	–	0.90
2024-07-24	4h12m	5h04m	22h38m	23h30m	–	–	0.81
2024-07-25	4h14m	5h06m	22h37m	23h28m	23h28m	23h43m	0.71
2024-07-26	4h16m	5h07m	22h35m	23h26m	23h26m	–	0.60
2024-07-27	4h18m	5h08m	22h34m	23h24m	23h24m	0h03m	0.49
2024-07-28	4h20m	5h10m	22h32m	23h22m	23h22m	0h26m	0.38
2024-07-29	4h22m	5h11m	22h31m	23h20m	23h20m	0h53m	0.28
2024-07-30	4h24m	5h13m	22h29m	23h18m	23h18m	1h26m	0.18
2024-07-31	4h26m	5h14m	22h28m	23h16m	23h16m	2h08m	0.11

Twilight calendar was generated using Cartes du Ciel (Sky Charts).

See my blog post: Twilight Zone for the definitions of the different periods of twilight here: https://bobmoler.wordpress.com/2018/09/27/.

NASA Calendar of Planetary Events

Jul  1  Mo            Venus: 7.4° E
     1  Mo   2:27 pm  Moon-Mars: 4.2° S
     2  Tu  11:31 am  Moon-Pleiades:  .3° N
     4  Th   8:08 pm  Moon North Dec.: 28.4° N
     5  Fr   1:59 am  Aphelion: 1.0167 AU
     5  Fr   6:57 pm  New Moon
     6  Sa   5:12 pm  Mercury-Beehive:  .1° S
     7  Su  12:04 pm  Moon-Beehive: 3.3° S
     7  Su   2:33 pm  Moon-Mercury: 3.5° S
     8  Mo   4:14 am  Jupiter-Aldebaran: 4.8° N
    12  Fr   4:12 am  Moon Apogee: 404400 km
    12  Fr   6:27 pm  Moon Descending Node
    13  Sa   6:49 pm  First Quarter
    13  Sa   9:48 pm  Moon-Spica: 1° S
    17  We   3:37 pm  Moon-Antares:  .2° S
    19  Fr   6:59 am  Moon South Dec.: 28.4° S
    20  Sa   3:35 pm  Mars-Pleiades: 4.8° S
    21  Su   6:17 am  Full Moon
    22  Mo   2:59 am  Mercury Elongation: 26.9° E
    24  We   1:43 am  Moon Perigee: 364900 km
    24  We   4:38 pm  Moon-Saturn:  .4° S
    24  We   9:40 pm  Mercury-Regulus: 2° S
    26  Fr   1:33 am  Moon Ascending Node
    27  Sa   5:44 pm  Delta Aquarid Shower: ZHR = 20
    27  Sa  10:52 pm  Last Quarter
    29  Mo   5:13 pm  Moon-Pleiades:  .1° N
Aug  1  Th            Venus: 15.9° E

All event times are given for UTC-4:00 Eastern Daylight Saving Time thereafter.

Sky Events Calendar by Fred Espenak and Sumit Dutta (NASA’s GSFC),
http://eclipse.gsfc.nasa.gov/SKYCAL/SKYCAL.html

If you go to the above site you can print out a list like the above for the entire year or calendar pages for your time zone.

Note that the site is now kept up for archival purposes. Fred Espenak retired from NASA several years ago and has his own site, AstroPixels, which contain the same information: http://astropixels.com/almanac/almanac.html. However it uses standard time all year.

Sun and Moon Rising and Setting Events

LU             Ephemeris of Sky Events for Interlochen/TC
July, 2024    Local time zone: EDT
+-----------------------------------------------------------------------+
| DATE |  SUN     SUN  DAYLIGHT|   TWILIGHT*    |MOON  RISE OR    ILLUM |
|      |  RISE    SET    HOURS |  END    START  |PHASE SET** TIME FRACTN|
+=======================================================================+
|Mon  1| 06:01a  09:31p  15:30 | 10:57p  04:36a |      Rise 02:50a   18%|
|Tue  2| 06:02a  09:31p  15:29 | 10:56p  04:36a |      Rise 03:26a   10%|
|Wed  3| 06:02a  09:31p  15:28 | 10:56p  04:37a |      Rise 04:13a    5%|
|Thu  4| 06:03a  09:31p  15:27 | 10:55p  04:38a |      Rise 05:10a    1%|
|Fri  5| 06:03a  09:30p  15:26 | 10:55p  04:39a |New   Set  09:59p    0%|
|Sat  6| 06:04a  09:30p  15:25 | 10:54p  04:40a |      Set  10:39p    1%|
+------+-----------------------+----------------+-----------------------+
|Sun  7| 06:05a  09:29p  15:24 | 10:53p  04:41a |      Set  11:10p    5%|
|Mon  8| 06:06a  09:29p  15:23 | 10:53p  04:42a |      Set  11:34p    9%|
|Tue  9| 06:06a  09:29p  15:22 | 10:52p  04:43a |      Set  11:53p   16%|
|Wed 10| 06:07a  09:28p  15:20 | 10:51p  04:44a |      Set  12:10a   23%|
|Thu 11| 06:08a  09:27p  15:19 | 10:50p  04:45a |      Set  12:26a   32%|
|Fri 12| 06:09a  09:27p  15:17 | 10:49p  04:46a |      Set  12:42a   41%|
|Sat 13| 06:10a  09:26p  15:16 | 10:48p  04:47a |F Qtr Set  12:58a   50%|
+------+-----------------------+----------------+-----------------------+
|Sun 14| 06:11a  09:25p  15:14 | 10:47p  04:49a |      Set  01:17a   60%|
|Mon 15| 06:12a  09:25p  15:13 | 10:46p  04:50a |      Set  01:40a   69%|
|Tue 16| 06:12a  09:24p  15:11 | 10:45p  04:51a |      Set  02:10a   78%|
|Wed 17| 06:13a  09:23p  15:09 | 10:44p  04:52a |      Set  02:49a   86%|
|Thu 18| 06:14a  09:22p  15:07 | 10:43p  04:54a |      Set  03:40a   92%|
|Fri 19| 06:15a  09:21p  15:06 | 10:41p  04:55a |      Set  04:45a   97%|
|Sat 20| 06:16a  09:21p  15:04 | 10:40p  04:56a |      Set  06:01a  100%|
+------+-----------------------+----------------+-----------------------+
|Sun 21| 06:17a  09:20p  15:02 | 10:39p  04:58a |Full  Rise 10:07p   99%|
|Mon 22| 06:18a  09:19p  15:00 | 10:38p  04:59a |      Rise 10:37p   97%|
|Tue 23| 06:19a  09:18p  14:58 | 10:36p  05:00a |      Rise 11:01p   91%|
|Wed 24| 06:20a  09:17p  14:56 | 10:35p  05:02a |      Rise 11:23p   83%|
|Thu 25| 06:21a  09:16p  14:54 | 10:33p  05:03a |      Rise 11:43p   74%|
|Fri 26| 06:23a  09:14p  14:51 | 10:32p  05:05a |      Rise 12:03a   63%|
|Sat 27| 06:24a  09:13p  14:49 | 10:30p  05:06a |L Qtr Rise 12:26a   51%|
+------+-----------------------+----------------+-----------------------+
|Sun 28| 06:25a  09:12p  14:47 | 10:29p  05:08a |      Rise 12:52a   40%|
|Mon 29| 06:26a  09:11p  14:45 | 10:27p  05:09a |      Rise 01:26a   30%|
|Tue 30| 06:27a  09:10p  14:42 | 10:26p  05:11a |      Rise 02:08a   20%|
|Wed 31| 06:28a  09:09p  14:40 | 10:24p  05:12a |      Rise 03:01a   12%|
+-----------------------------------------------------------------------+
* Nautical Twilight
** Moonrise or moonset, whichever occurs between sunset and sunrise

Generated using my LookingUp for DOS app.